a fanciful idea about a better form of cancellation in C#

cancellation.cs

// a fanciful idea about a better form of cancellation in C#

try
{
    Foo(cancellationToken);
}
catch (Cancellation cancellation) // System.Cancellation - does NOT inherit from System.Exception, but still has a stack trace, etc.
{
}
catch (Exception ex)
{
}
finally
{
}

// cancel is a new keyword and param modifier
// more than one cancel param can be declared, although that's probably quite unusual
// the param is implicitly an optional CancellationToken
// the default value is CancellationToken.None
// the return type of Foo would probably be Task-like in most cases, but that's irrelevant
void Foo(cancel cancellationToken)
{
    // can still check if the token is cancelled, etc.
    if (cancellationToken.IsCancellationRequested)
    {
    }

    // can still create linked token sources, etc.
    var src = CancellationTokenSource.CreateLinkedTokenSource(cancellationToken, myToken);

    // can only throw a Cancellation with yield cancel, a new keyword combination
    // yield cancel only throws a Cancellation if at least one cancel arg has IsCancellationRequested == true
    yield cancel;
}